Put in a new 383 stroker motor. 380 HP at rear wheels. Prior engine [ ZZ4 ] modified made 330Hp at rear wheels and never saw over 220* water temp. New engine goes to 240 after 3 laps. Course about 2.2 miles. If I continue the temp keeps going up. Am using stock rad.
What's a good replacement that will do the job without a lot of fab work?

 

Every time I see one of these cars at the track I mention to the owner to keep the water temp down and get a big radiator if they will continue to do track events. I've seen several go home on the flatbed with blown head gaskets. After a better radiator use a high flow water pump. I would be nervous in the 220's let alone 240's.

 

Hi,
how do you messure water temps? If it´s the stock digital dash cluster, please be aware that it shows to much temp. Verify this with a scan tool an you will see the temp 20 degree down.

Besides that, you could try water wetter. This should bring temps down around 16 to 20 degree. A bigger rad is of course a good idea.

To much ignition advance will quickly show high water temps. Check that.

 

what about the fan, is it working ?

 

I used a Dewitt radiator, it fit well and works well but they are expensive.

 

I have one. Works, drops in, but pricey.

You've increased HP 35%, but still using the stock cooling system capacity. There is the problem. You're right to want more radiator...esp for track use.



No it won't. Too much ignition advance will cause other symptoms first (like detonation). OP needs more radiator for more displacement, more power, and track use.


Fan doesn't run over ~30mph, so it's probably not working on the track.

 

Toms right
Bigger motor
More heat
Need more radiator period

Engine oil cooler a bonus whatever it takes
Ea rod is travelling farther up and down for ea revolution the oil will get hotter too from more friction

 

In my race car I just use distilled water with about 2 qt's green anti freeze and 2 water wetter,just have to change when cold weather sets in.Car cooled better and ran cooler like that good luck,big radiators work well.

 

I have a 400 RWHP 383 in my track car - Dewitts radiator (and no A/C coil) and I have no overheating problems. The Dewitts isn't a drop in - the shrouding needs a few mods to make it work, but if you got to their website it should have the details of what needs to be modified. I've heard very good things about Ron Davis Racing Rads as well - neither the Dewitts or the Ron Davis are cheap. Believe me - after you get the front six bolts holding the fan shroud out - the mods won't seem like much of a big deal. I did not put all six bolts back - I think I went with 4.

If you haven't already done so - pull the rad out and verify that there is no crud in the air box (most C4's get crudded up after a while). Also - do a full coolant flush including pulling the Knock sensors / block drains - you might be surprised what comes out of the block drains the first time you open them up. I know it's a "new" motor - but if the block was tanked - there might be a lot of crud in there...

I also recommend wiring in a switch to allow you to run the electric fans manually on a track car - that way you can switch them ON manually as you come off the track, and run them in the pits as needed. Once the car is doing over about 35 - 40 mph - the electric fans are basically along for the ride - but at pit / paddock speeds they do help.

 

An aftermarket air dam might help some...look up a "big mouth" air dam. I have no experience myself with these, but have heard good things.

 

I'm running a Ron Davis race radiator. No heat problems here.